/* $FreeBSD: src/sys/msdosfs/msdosfs_denode.c,v 1.47.2.3 2002/08/22 16:20:15 trhodes Exp $ */ /* $DragonFly: src/sys/vfs/msdosfs/msdosfs_denode.c,v 1.35 2008/06/08 07:56:06 nth Exp $ */ /* $NetBSD: msdosfs_denode.c,v 1.28 1998/02/10 14:10:00 mrg Exp $ */ /*- * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank. * Copyright (C) 1994, 1995, 1997 TooLs GmbH. * All rights reserved. * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below). * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by TooLs GmbH. * 4. The name of TooLs GmbH may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /* * Written by Paul Popelka (paulp@uts.amdahl.com) * * You can do anything you want with this software, just don't say you wrote * it, and don't remove this notice. * * This software is provided "as is". * * The author supplies this software to be publicly redistributed on the * understanding that the author is not responsible for the correct * functioning of this software in any circumstances and is not liable for * any damages caused by this software. * * October 1992 */ #include #include #include #include #include #include #include #include #include #include #include "bpb.h" #include "msdosfsmount.h" #include "direntry.h" #include "denode.h" #include "fat.h" static int msdosfs_hashins (struct denode *dep); static void msdosfs_hashrem (struct denode *dep); static MALLOC_DEFINE(M_MSDOSFSNODE, "MSDOSFS node", "MSDOSFS vnode private part"); /* * Hash table caching denode instances. * * denodes are keyed by the disk location (cluster num, entry offset) of the * directory entry of the file they represent. * * denodes representing deleted but still opened files are left in this cache * until reclaimed. Deleted directory entries can be reused when files are * renamed or new files created. As a consequence, several denodes associated * with the same entry may coexist in this cache as long as a single one of * them map to an existing file (de_refcnt > 0). * * R/w access to this cache is protected by dehash_token. */ static struct denode **dehashtbl; static u_long dehash; /* size of hash table - 1 */ #define DEHASH(dev, dcl, doff) (dehashtbl[(minor(dev) + (dcl) + (doff) / \ sizeof(struct direntry)) & dehash]) static struct lwkt_token dehash_token; union _qcvt { quad_t qcvt; long val[2]; }; #define SETHIGH(q, h) { \ union _qcvt tmp; \ tmp.qcvt = (q); \ tmp.val[_QUAD_HIGHWORD] = (h); \ (q) = tmp.qcvt; \ } #define SETLOW(q, l) { \ union _qcvt tmp; \ tmp.qcvt = (q); \ tmp.val[_QUAD_LOWWORD] = (l); \ (q) = tmp.qcvt; \ } static struct denode * msdosfs_hashget (cdev_t dev, u_long dirclust, u_long diroff); /*ARGSUSED*/ int msdosfs_init(struct vfsconf *vfsp) { dehash = 16; while (dehash < desiredvnodes) dehash <<= 1; dehashtbl = kmalloc(sizeof(void *) * dehash, M_MSDOSFSMNT, M_WAITOK|M_ZERO); --dehash; lwkt_token_init(&dehash_token, 1); return (0); } int msdosfs_uninit(struct vfsconf *vfsp) { if (dehashtbl) kfree(dehashtbl, M_MSDOSFSMNT); return (0); } static struct denode * msdosfs_hashget(cdev_t dev, u_long dirclust, u_long diroff) { struct denode *dep; struct vnode *vp; lwkt_gettoken(&dehash_token); loop: for (dep = DEHASH(dev, dirclust, diroff); dep; dep = dep->de_next) { if (dirclust != dep->de_dirclust || diroff != dep->de_diroffset || dev != dep->de_dev || dep->de_refcnt <= 0) { continue; } vp = DETOV(dep); if (vget(vp, LK_EXCLUSIVE)) goto loop; /* * We must check to see if the inode has been ripped * out from under us after blocking. */ for (dep = DEHASH(dev, dirclust, diroff); dep; dep = dep->de_next) { if (dirclust == dep->de_dirclust && diroff == dep->de_diroffset && dev == dep->de_dev && dep->de_refcnt > 0) { break; } } if (dep == NULL || DETOV(dep) != vp) { vput(vp); goto loop; } lwkt_reltoken(&dehash_token); return (dep); } lwkt_reltoken(&dehash_token); return (NULL); } /* * Try to insert specified denode into the hash table. Return 0 on success * and EBUSY if there is already a denode with the same key. */ static int msdosfs_hashins(struct denode *dep) { struct denode **depp, *deq; lwkt_gettoken(&dehash_token); depp = &DEHASH(dep->de_dev, dep->de_dirclust, dep->de_diroffset); while ((deq = *depp) != NULL) { if (deq->de_dev == dep->de_dev && deq->de_dirclust == dep->de_dirclust && deq->de_diroffset == dep->de_diroffset && deq->de_refcnt > 0) { lwkt_reltoken(&dehash_token); return(EBUSY); } depp = &deq->de_next; } dep->de_next = NULL; *depp = dep; lwkt_reltoken(&dehash_token); return(0); } static void msdosfs_hashrem(struct denode *dep) { struct denode **depp, *deq; lwkt_gettoken(&dehash_token); depp = &DEHASH(dep->de_dev, dep->de_dirclust, dep->de_diroffset); while ((deq = *depp) != NULL) { if (dep == deq) break; depp = &deq->de_next; } KKASSERT(dep == deq); *depp = dep->de_next; dep->de_next = NULL; lwkt_reltoken(&dehash_token); } void msdosfs_reinsert(struct denode *ip, u_long new_dirclust, u_long new_diroffset) { int error; lwkt_gettoken(&dehash_token); msdosfs_hashrem(ip); ip->de_dirclust = new_dirclust; ip->de_diroffset = new_diroffset; error = msdosfs_hashins(ip); KASSERT(!error, ("msdosfs_reinsert: insertion failed %d", error)); lwkt_reltoken(&dehash_token); } /* * If deget() succeeds it returns with the gotten denode locked(). * * pmp - address of msdosfsmount structure of the filesystem containing * the denode of interest. The pm_dev field and the address of * the msdosfsmount structure are used. * dirclust - which cluster bp contains, if dirclust is 0 (root directory) * diroffset is relative to the beginning of the root directory, * otherwise it is cluster relative. * diroffset - offset past begin of cluster of denode we want * depp - returns the address of the gotten denode. */ int deget(struct msdosfsmount *pmp, /* so we know the maj/min number */ u_long dirclust, /* cluster this dir entry came from */ u_long diroffset, /* index of entry within the cluster */ struct denode **depp) /* returns the addr of the gotten denode */ { int error; cdev_t dev = pmp->pm_dev; struct mount *mntp = pmp->pm_mountp; struct direntry *direntptr; struct denode *ldep; struct vnode *nvp; struct buf *bp; struct timeval tv; #ifdef MSDOSFS_DEBUG kprintf("deget(pmp %p, dirclust %lu, diroffset %lx, depp %p)\n", pmp, dirclust, diroffset, depp); #endif /* * On FAT32 filesystems, root is a (more or less) normal * directory */ if (FAT32(pmp) && dirclust == MSDOSFSROOT) dirclust = pmp->pm_rootdirblk; again: /* * See if the denode is in the denode cache. Use the location of * the directory entry to compute the hash value. For subdir use * address of "." entry. For root dir (if not FAT32) use cluster * MSDOSFSROOT, offset MSDOSFSROOT_OFS * * NOTE: The check for de_refcnt > 0 below insures the denode being * examined does not represent an unlinked but still open file. * These files are not to be accessible even when the directory * entry that represented the file happens to be reused while the * deleted file is still open. */ ldep = msdosfs_hashget(dev, dirclust, diroffset); if (ldep) { *depp = ldep; return (0); } /* * Do the MALLOC before the getnewvnode since doing so afterward * might cause a bogus v_data pointer to get dereferenced * elsewhere if MALLOC should block. */ MALLOC(ldep, struct denode *, sizeof(struct denode), M_MSDOSFSNODE, M_WAITOK | M_ZERO); /* * Directory entry was not in cache, have to create a vnode and * copy it from the passed disk buffer. */ /* getnewvnode() does a vref() on the vnode */ error = getnewvnode(VT_MSDOSFS, mntp, &nvp, VLKTIMEOUT, 0); if (error) { *depp = NULL; FREE(ldep, M_MSDOSFSNODE); return error; } ldep->de_vnode = nvp; ldep->de_flag = 0; ldep->de_devvp = 0; ldep->de_dev = dev; ldep->de_dirclust = dirclust; ldep->de_diroffset = diroffset; fc_purge(ldep, 0); /* init the fat cache for this denode */ /* * Insert the denode into the hash queue. If a collision occurs * throw away the vnode and try again. */ error = msdosfs_hashins(ldep); if (error == EBUSY) { nvp->v_type = VBAD; vx_put(nvp); kfree(ldep, M_MSDOSFSNODE); goto again; } else if (error) { nvp->v_type = VBAD; vx_put(nvp); kfree(ldep, M_MSDOSFSNODE); *depp = NULL; return (EINVAL); } nvp->v_data = ldep; ldep->de_pmp = pmp; ldep->de_refcnt = 1; /* * Copy the directory entry into the denode area of the vnode. */ if ((dirclust == MSDOSFSROOT || (FAT32(pmp) && dirclust == pmp->pm_rootdirblk)) && diroffset == MSDOSFSROOT_OFS) { /* * Directory entry for the root directory. There isn't one, * so we manufacture one. We should probably rummage * through the root directory and find a label entry (if it * exists), and then use the time and date from that entry * as the time and date for the root denode. */ vsetflags(nvp, VROOT); /* should be further down XXX */ ldep->de_Attributes = ATTR_DIRECTORY; ldep->de_LowerCase = 0; if (FAT32(pmp)) ldep->de_StartCluster = pmp->pm_rootdirblk; /* de_FileSize will be filled in further down */ else { ldep->de_StartCluster = MSDOSFSROOT; ldep->de_FileSize = pmp->pm_rootdirsize * DEV_BSIZE; } /* * fill in time and date so that dos2unixtime() doesn't * spit up when called from msdosfs_getattr() with root * denode */ ldep->de_CHun = 0; ldep->de_CTime = 0x0000; /* 00:00:00 */ ldep->de_CDate = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT) | (1 << DD_DAY_SHIFT); /* Jan 1, 1980 */ ldep->de_ADate = ldep->de_CDate; ldep->de_MTime = ldep->de_CTime; ldep->de_MDate = ldep->de_CDate; /* leave the other fields as garbage */ } else { error = readep(pmp, dirclust, diroffset, &bp, &direntptr); if (error) { /* * The denode does not contain anything useful, so * it would be wrong to leave it on its hash chain. * Arrange for vput() to just forget about it. */ ldep->de_Name[0] = SLOT_DELETED; nvp->v_type = VBAD; vx_put(nvp); *depp = NULL; return (error); } DE_INTERNALIZE(ldep, direntptr); brelse(bp); } /* * Fill in a few fields of the vnode and finish filling in the * denode. Then return the address of the found denode. */ if (ldep->de_Attributes & ATTR_DIRECTORY) { /* * Since DOS directory entries that describe directories * have 0 in the filesize field, we take this opportunity * to find out the length of the directory and plug it into * the denode structure. */ u_long size; /* * XXX Sometimes, these arrives that . entry have cluster * number 0, when it shouldn't. Use real cluster number * instead of what is written in directory entry. */ if ((diroffset == 0) && (ldep->de_StartCluster != dirclust)) { kprintf("deget(): . entry at clust %ld != %ld\n", dirclust, ldep->de_StartCluster); ldep->de_StartCluster = dirclust; } nvp->v_type = VDIR; if (ldep->de_StartCluster != MSDOSFSROOT) { error = pcbmap(ldep, 0xffff, NULL, &size, NULL); if (error == E2BIG) { ldep->de_FileSize = de_cn2off(pmp, size); error = 0; } else kprintf("deget(): pcbmap returned %d\n", error); } } else { nvp->v_type = VREG; } getmicrouptime(&tv); SETHIGH(ldep->de_modrev, tv.tv_sec); SETLOW(ldep->de_modrev, tv.tv_usec * 4294); ldep->de_devvp = pmp->pm_devvp; vref(ldep->de_devvp); vinitvmio(nvp, ldep->de_FileSize, PAGE_SIZE, -1); /* * Leave nvp locked and refd so the returned inode is effectively * locked and refd. */ *depp = ldep; return (0); } int deupdat(struct denode *dep, int waitfor) { int error; struct buf *bp; struct direntry *dirp; struct timespec ts; if (DETOV(dep)->v_mount->mnt_flag & MNT_RDONLY) return (0); getnanotime(&ts); DETIMES(dep, &ts, &ts, &ts); if ((dep->de_flag & DE_MODIFIED) == 0) return (0); dep->de_flag &= ~DE_MODIFIED; if (dep->de_Attributes & ATTR_DIRECTORY) return (0); if (dep->de_refcnt <= 0) return (0); error = readde(dep, &bp, &dirp); if (error) return (error); DE_EXTERNALIZE(dirp, dep); if (waitfor) return (bwrite(bp)); else { bdwrite(bp); return (0); } } /* * Truncate the file described by dep to the length specified by length. */ int detrunc(struct denode *dep, u_long length, int flags) { int error; int allerror; u_long eofentry; u_long chaintofree; daddr_t bn, cn; int boff; int isadir = dep->de_Attributes & ATTR_DIRECTORY; struct buf *bp; struct msdosfsmount *pmp = dep->de_pmp; #ifdef MSDOSFS_DEBUG kprintf("detrunc(): file %s, length %lu, flags %x\n", dep->de_Name, length, flags); #endif /* * Disallow attempts to truncate the root directory since it is of * fixed size. That's just the way dos filesystems are. We use * the VROOT bit in the vnode because checking for the directory * bit and a startcluster of 0 in the denode is not adequate to * recognize the root directory at this point in a file or * directory's life. */ if ((DETOV(dep)->v_flag & VROOT) && !FAT32(pmp)) { kprintf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n", dep->de_dirclust, dep->de_diroffset); return (EINVAL); } if (dep->de_FileSize < length) { vnode_pager_setsize(DETOV(dep), length); return deextend(dep, length); } /* * If the desired length is 0 then remember the starting cluster of * the file and set the StartCluster field in the directory entry * to 0. If the desired length is not zero, then get the number of * the last cluster in the shortened file. Then get the number of * the first cluster in the part of the file that is to be freed. * Then set the next cluster pointer in the last cluster of the * file to CLUST_EOFE. */ if (length == 0) { chaintofree = dep->de_StartCluster; dep->de_StartCluster = 0; eofentry = ~0; } else { error = pcbmap(dep, de_clcount(pmp, length) - 1, NULL, &eofentry, NULL); if (error) { #ifdef MSDOSFS_DEBUG kprintf("detrunc(): pcbmap fails %d\n", error); #endif return (error); } } fc_purge(dep, de_clcount(pmp, length)); /* * If the new length is not a multiple of the cluster size then we * must zero the tail end of the new last cluster in case it * becomes part of the file again because of a seek. */ if ((boff = length & pmp->pm_crbomask) != 0) { if (isadir) { bn = xcntobn(pmp, eofentry); error = bread(pmp->pm_devvp, de_bntodoff(pmp, bn), pmp->pm_bpcluster, &bp); } else { cn = de_cluster(pmp, length); error = bread(DETOV(dep), de_cn2doff(pmp, cn), pmp->pm_bpcluster, &bp); } if (error) { brelse(bp); #ifdef MSDOSFS_DEBUG kprintf("detrunc(): bread fails %d\n", error); #endif return (error); } /* * is this the right place for it? */ bzero(bp->b_data + boff, pmp->pm_bpcluster - boff); if (flags & IO_SYNC) bwrite(bp); else bdwrite(bp); } /* * Write out the updated directory entry. Even if the update fails * we free the trailing clusters. */ dep->de_FileSize = length; if (!isadir) dep->de_flag |= DE_UPDATE|DE_MODIFIED; allerror = vtruncbuf(DETOV(dep), length, pmp->pm_bpcluster); #ifdef MSDOSFS_DEBUG if (allerror) kprintf("detrunc(): vtruncbuf error %d\n", allerror); #endif error = deupdat(dep, 1); if (error && (allerror == 0)) allerror = error; #ifdef MSDOSFS_DEBUG kprintf("detrunc(): allerror %d, eofentry %lu\n", allerror, eofentry); #endif /* * If we need to break the cluster chain for the file then do it * now. */ if (eofentry != ~0) { error = fatentry(FAT_GET_AND_SET, pmp, eofentry, &chaintofree, CLUST_EOFE); if (error) { #ifdef MSDOSFS_DEBUG kprintf("detrunc(): fatentry errors %d\n", error); #endif return (error); } fc_setcache(dep, FC_LASTFC, de_cluster(pmp, length - 1), eofentry); } /* * Now free the clusters removed from the file because of the * truncation. */ if (chaintofree != 0 && !MSDOSFSEOF(pmp, chaintofree)) freeclusterchain(pmp, chaintofree); return (allerror); } /* * Extend the file described by dep to length specified by length. */ int deextend(struct denode *dep, u_long length) { struct msdosfsmount *pmp = dep->de_pmp; u_long count; int error; /* * The root of a DOS filesystem cannot be extended. */ if ((DETOV(dep)->v_flag & VROOT) && !FAT32(pmp)) return (EINVAL); /* * Directories cannot be extended. */ if (dep->de_Attributes & ATTR_DIRECTORY) return (EISDIR); if (length <= dep->de_FileSize) panic("deextend: file too large"); /* * Compute the number of clusters to allocate. */ count = de_clcount(pmp, length) - de_clcount(pmp, dep->de_FileSize); if (count > 0) { if (count > pmp->pm_freeclustercount) return (ENOSPC); error = extendfile(dep, count, NULL, NULL, DE_CLEAR); if (error) { /* truncate the added clusters away again */ detrunc(dep, dep->de_FileSize, 0); return (error); } } dep->de_FileSize = length; dep->de_flag |= DE_UPDATE|DE_MODIFIED; return (deupdat(dep, 1)); } /* * msdosfs_reclaim(struct vnode *a_vp) */ int msdosfs_reclaim(struct vop_reclaim_args *ap) { struct vnode *vp = ap->a_vp; struct denode *dep = VTODE(vp); #ifdef MSDOSFS_DEBUG kprintf("msdosfs_reclaim(): dep %p, file %s, refcnt %ld\n", dep, dep ? (char *)dep->de_Name : "?", dep ? dep->de_refcnt : -1); #endif if (prtactive && vp->v_sysref.refcnt > 1) vprint("msdosfs_reclaim(): pushing active", vp); /* * Remove the denode from its hash chain. */ vp->v_data = NULL; if (dep) { msdosfs_hashrem(dep); if (dep->de_devvp) { vrele(dep->de_devvp); dep->de_devvp = 0; } kfree(dep, M_MSDOSFSNODE); } return (0); } /* * msdosfs_inactive(struct vnode *a_vp) */ int msdosfs_inactive(struct vop_inactive_args *ap) { struct vnode *vp = ap->a_vp; struct denode *dep = VTODE(vp); int error = 0; #ifdef MSDOSFS_DEBUG kprintf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep, (dep ? dep->de_Name[0] : 0)); #endif if (prtactive && vp->v_sysref.refcnt > 1) vprint("msdosfs_inactive(): pushing active", vp); /* * Ignore denodes related to stale file handles. */ if (dep == NULL || dep->de_Name[0] == SLOT_DELETED) goto out; /* * If the file has been deleted and it is on a read/write * filesystem, then truncate the file, and mark the directory slot * as empty. (This may not be necessary for the dos filesystem.) */ #ifdef MSDOSFS_DEBUG kprintf("msdosfs_inactive(): dep %p, refcnt %ld, mntflag %x, MNT_RDONLY %x\n", dep, dep->de_refcnt, vp->v_mount->mnt_flag, MNT_RDONLY); #endif if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) { error = detrunc(dep, (u_long) 0, 0); dep->de_flag |= DE_UPDATE; dep->de_Name[0] = SLOT_DELETED; } deupdat(dep, 0); out: /* * If we are done with the denode, reclaim it * so that it can be reused immediately. */ #ifdef MSDOSFS_DEBUG kprintf("msdosfs_inactive(): v_sysrefs %d, de_Name[0] %x\n", vp->v_sysref.refcnt, (dep ? dep->de_Name[0] : 0)); #endif if (dep == NULL || dep->de_Name[0] == SLOT_DELETED) vrecycle(vp); return (error); }